In the explanations to the figures, the sample numbers and slide designations (in the form "Ph.2," "Sl.1," "Cse.2," etc.) indicate preparations in our collection at Scripps Institution of Oceanography (or, in the case of types specimens, preparations to be deposited in the U.S. National Museum, Washington, D.C.) and designations in the form "R45/1" indicate England Finder positions of the illustrated specimens on the slides (Riedel and Foreman, 1961).